Metal Lathe Parts

[bassethound]

Why the bloody hell do the mini chinese metal lathes use plastic gear cogs looks like I got to pay over 12 quid for a bloody bit of plastc just so I can use the power feed spindle need to find a metal one some time!

 

[Bigblackdog]

how annoying.

i have just bought a metal lathe myself- should get it tomorrow. I looked at the chinese options, but went vintage in the end.

 

[Buckeye]

They usually use plastic as a sacrificial part so that you don't screw up the lathe if you don't stop the feed in time and hit something solid although there should be a sacrificial pin which is cheaper. I used to have a processing machine and it had a plastic sacrificial cog on the drive, if anything ore than two prints got stuck it would shear the bleeding thing and I had to buy another until I hit on the idea of making a mould of the cog and casting it with polyurethane resin, it was much stronger than the originals and after the first one didn't cost anywhere near the price of buying one.

Peter

 

[bassethound]

They usually use plastic as a sacrificial part so that you don't screw up the lathe if you don't stop the feed in time and hit something solid although there should be a sacrificial pin which is cheaper. I used to have a processing machine and it had a plastic sacrificial cog on the drive, if anything ore than two prints got stuck it would shear the bleeding thing and I had to buy another until I hit on the idea of making a mould of the cog and casting it with polyurethane resin, it was much stronger than the originals and after the first one didn't cost anywhere near the price of buying one.

Peter

Yes it's a bit of a pain Peter, i may even try casting a Aluminium one using the old one as a pattern and cut the teeth out with the Dremel, that should be soft enough, if I feel like doing it

 

[chas_41_uk]

It's not just the Chinese Ted. My Emco Compact 5 has plastic gears and that was made in Austria in the 1970's-80's

 

[Penpal]

Maybe this points to choice at the time of purchase when others indicate they are about to buy suggest the extra in metal gears. Strangely new users of metal lathes need all the safety as Peter has said such a small amount to fix in plastic on the other hand.

Similar thoughts abound with pens using plastic and metal threads, the weakest parts of and screw pen both pens and lathes get a tough work out.

Peter.

 

[Buckeye]

Yes it's a bit of a pain Peter, i may even try casting a Aluminium one using the old one as a pattern and cut the teeth out with the Dremel, that should be soft enough, if I feel like doing it

One of my plans is to cut a back gear for my lathe that I am missing, so if I ever get a mill and dividing head or similar then I will have a go at it, if I am successful I will let you know, how many teeth are on your cog?

Peter

 

[bassethound]

One of my plans is to cut a back gear for my lathe that I am missing, so if I ever get a mill and dividing head or similar then I will have a go at it, if I am successful I will let you know, how many teeth are on your cog?

Peter

There are 80 teeth Peter and has a key cut in the bore to hold it in! not a big deal with a mill I would think.

 

[wm460]

There are 80 teeth Peter and has a key cut in the bore to hold it in! not a big deal with a mill I would think.

Phenolic gear cutting - YouTube

Phenolic gear cutting #2 - YouTube

 

[Buckeye]

I Have a look at this video on making a keyway cutter for the lathe, I have seen other broaching videos but this is quite good.

Peter

Spare Parts #1 - Making, Hardening And Tempering A Keyway Cutter For The Lathe - YouTube

 

[Penpal]

Two very exciting videos Mark thanks mate.

Peter.

 

[21William]

Why the bloody hell do the mini chinese metal lathes use plastic gear cogs.

Injection moulded plastic gears are massively cheaper to produce than cast iron or steel gears.

Unless the gears are an odd size/pitch there's probably someone out there that can supply steel ones the same size but they may not be cheap.

 

[wm460]

Thanks for that video Peter, I haven't seen that one before.

Another one that may interest people.

Spare Parts #13 - Making A Square Broach - YouTube

 

[bassethound]

Yes saw a few videos last night about those then saw one about making a mould with RV rubber and casting with resin
still too much messing about for me lol plastic it is for now..